What is torsade de pointes and what causes it?
Torsades de Pointes is a specific type of ventricular tachycardia, or fast heart rhythm that begins in your heart ventricles. You can get it if you inherited Long QT syndrome or if you take certain medicines. Although Torsades de Pointes can be deadly if untreated, treatment greatly improves your outlook.
What is torsade de pointes symptoms?
Around 50% of patients with Torsades de Pointes are asymptomatic. The most common symptoms reported are syncope, palpitations, and dizziness. However, cardiac death is the presenting symptom in up to 10% of patients. Patients with Jervell and Lange Nielsen syndrome may have a history of deafness.
What is the most common cause of torsades de pointes?
The most common causes of acquired long QT syndrome are medications and electrolyte disorders (eg, hypokalemia, hypomagnesemia). Drug-associated torsade de pointes is relatively rare, but is becoming increasingly common; its incidence is as high as 2-3% with certain drugs.
What is the best treatment for torsades de pointes?
Intravenous magnesium sulfate, a relatively new mode of therapy for torsade de pointes, was proven to be extremely effective and is now regarded as the treatment of choice for this arrhythmia.
What happens to the heart during Torsades de Pointes?
In the case of torsades de pointes (TdP), the heart’s two lower chambers, called the ventricles, beat faster than and out of sync with the upper chambers, called the atria. An abnormal heart rhythm is called an arrhythmia. When the heart beats much faster than normal, the condition is called tachycardia.
What medications cause torsades Depointes?
The list of drugs known to cause TdP that require a dose adjustment for patients with acute kidney injury or chronic kidney disease include: ciprofloxacin, disopyramide, dofetilide, flecainide, fluconazole, levofloxacin, procainamide, and sotalol.
Is QT prolongation permanent?
Some forms of long QT syndrome result from a genetic mutation that is passed down through families (inherited). If an underlying medical condition or medication causes it, it’s called acquired long QT syndrome. This type of long QT syndrome is usually reversible when the underlying cause is identified.
What happens to the heart during torsades de pointes?
What’s another name for torsades de pointes?
When the heart beats faster than usual, as in a case of torsades de pointes, it is called tachycardia. Torsades de pointes is French for “twisting of points” and refers to when the heart’s two lower chambers or ventricles, beat faster than the upper chambers, which are known as the atria.
How does QT prolongation cause torsades?
Torsade de pointes is widely thought to be triggered by reactivation of calcium channels, reactivation of a delayed sodium current, or a decreased outward potassium current that results in early afterdepolarization (EAD), in a condition with enhanced TDR usually associated with a prolonged QT interval.
What does torsades feel like?
You may suddenly feel your heart beating faster than normal, even when you’re at rest. In some TdP episodes, you may feel light-headed and faint. In the most serious cases, TdP can cause cardiac arrest or sudden cardiac death. It’s also possible have an episode (or more than one) that resolves quickly.
How do fluoroquinolones cause QT prolongation?
Fluoroquinolones prolong the QT interval by blocking voltage-gated potassium channels, especially the rapid component of the delayed rectifier potassium current I(Kr), expressed by HERG (the human ether-a-go-go-related gene).